16799561 has 4 divisors (see below), whose sum is σ = 16861824. Its totient is φ = 16737300.

The previous prime is 16799557. The next prime is 16799567. The reversal of 16799561 is 16599761.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 16599761 = 397 ⋅41813.

It is a cyclic number.

It is not a de Polignac number, because 16799561 - 2² = 16799557 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (16799567) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 30725 + ... + 31266.

It is an arithmetic number, because the mean of its divisors is an integer number (4215456).

Almost surely, 2^16799561 is an apocalyptic number.

It is an amenable number.

16799561 is a deficient number, since it is larger than the sum of its proper divisors (62263).

16799561 is an equidigital number, since it uses as much as digits as its factorization.

16799561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 62262.

The product of its digits is 102060, while the sum is 44.

The square root of 16799561 is about 4098.7267535175. The cubic root of 16799561 is about 256.1136021279.

The spelling of 16799561 in words is "sixteen million, seven hundred ninety-nine thousand, five hundred sixty-one".